The Bolivian president, Evo Morales, has secured a sweeping land reform bill with the help of thousands of indigenous peasants who marched on the capital, La Paz.

To the jubilation of his supporters, Mr Morales signed the bill into law at a midnight ceremony last night after overcoming fierce resistance from senators representing large landowners.

The law is intended to reverse centuries of discrimination against the indigenous majority by seizing 77,000 square miles of land - an area around three-quarters the size of Britain - deemed unproductive or illegally owned and redistributing it to the poor.

"This is the struggle of our ancestors, the struggle for power and territory," Mr Morales said. "Now, the change is in our hands."

It was another victory for Latin America's first indigenous president, who has been on a roll since persuading oil and gas multinationals to give most of their Bolivian revenues to the state.

Following his election last December, the former coca farmer pushed radical land reform through the lower house which is controlled by his Movement Toward Socialism (MAS) party.

But it stalled in the opposition-controlled senate where MAS had just 12 out of 27 seats. An opposition boycott prevented the assembly reaching its 14-seat quorum.

Mr Morales threatened to bypass the senate with a presidential decree, and the pressure increased when 3,000 peasants, many in ponchos and straw hats and chewing coca leaves, marched into the capital to back him.

Yesterday the opposition buckled. A senator from the conservative Podemos party and assistants representing two senators from smaller parties voted with MAS to pass the bill.

Large landowners vowed to resist the redistribution.

Separately, civil society leaders in eight out of nine provinces called for a general strike this Friday to protest the government's control of an assembly tasked with drafting a new constitution.